External (boot) Thunderbolt 3 SSD performance

[golfgirlgolf]

I have a quick question on SSD speeds -

Setup - 2019 IMac 3.7 GHz 6-Core Intel Core i5 64 GB - booting from -

OWC Envoy Express Thunderbolt 3 Bus-Powered Enclosure for NVMe M.2 SSD
with
SAMSUNG 970 EVO PLUS M.2 2280 2TB PCIe Gen 3.0 x4, NVMe 1.3 V-NAND 3-bit MLC Internal Solid State Drive (SSD) MZ-V7S2T0B/AM
(I also have a 1TB version of this in another enclosure)

The W/R performance I'm getting is about 850/1500 - is that about all I can expect? It's certainly a huge improvement over the iMac's internal HDD but I do see some reports online of higher speeds (likely different than my setup) so if that's possible I'd appreciate any pointers! Maybe a Mac Studio is the answer - ha!

 

[Fishrrman]

What are you going to use this drive for?

Read speeds look fine.
Write speeds look a little slower than might be expected, but how "warm" does the enclosure get with extended writes?

NVME SSDs seem to run hotter than do 2.5" SATA SSDs. Of course, they're faster, too.
I believe some nvme SSDs will "throttle back the speed" if they start running to hot for too long.
They still "keep going", but do slow down somewhat.

 

[QuietOC]

Are you using another device on the same bus?

Since you are booting from this drive, maybe Mac OS was still using it.

The 2TB EVO Plus has an issue with Thunderbolt where it writes at slower speeds.

 

[golfgirlgolf]

Thanks everyone. I returned the 970 EVO PLUS and got the 980 PRO - also returned the Envoy Express enclosure and got the ACASIS (these were recommended / known working - on Digital Photography Review) - now it's fantastic!

The use is a boot SSD and to run slow processes faster - Photoshop and Lightroom in particular. Both are power hogs and need fast access to perform well.